Application of Some Physical Techniques for Forensic Discrimination of Printer Toner

Abstract

T HE DOCUMENTS examiner had trouble with forensic discrimination between types of toner using a single analysis method. In our study seven samples of toner removed from laser printers of various and same brands of different models will be analysed using more than one method as Fourier transform infrared (FT-IR), Raman spectroscopy, X-ray fluorescence (XRF) and X-ray diffraction (XRD) to distinguish between different toner samples and applying apply all analysis data for forensic evidence. Results of FT-IR analysis show that all toner samples of HP brand had the same polymeric resin. Raman spectroscopy used to differentiate between toner samples had the same polymeric resin in FT-IR analysis by comparing their Raman spectrum.Toner samples of HP 2300 and HP 4700 printers were indistinguishable by using results of FT-IR and Raman spectroscopy,therefore, more elemental analysis will be required. XRF used to differentiate between indistinguishable toner samples of HP 2300 and HP 4700 printers by FT-IR and Raman spectroscopy. Also for all toner samples, results of XRFshown showed that iron, silicon, cupper, calcium, and ruthenium were the major percent elements present in toner. The results of XRD show thatt here are common compounds (phases) between the analyzed tonersamples and the composition for major elementspresent were oxides.

Using the Physical and Chemical Characterization for the Ink of Laser Printer and Ballpoint Pen in Determination the Sequence of Their Intersection

“…The second important physical property observed under the digital microscope is the ink and toner gloss. The toner has a gloss property due to the presence of wax in its composition [10,[25][26][27] and ballpoint pen inks also have the same property due to the presence of luminescent substances in its composition [4]. The gloss of both toner and ballpoint pen ink discontinued when the toner intersects ink as in Fig.…”

“…Although, the ballpoint pens are still very famous use and widespread kind of writing device in various documents [2][3][4]. In addition, laser printouts always used with ballpoint pen ink in daily routine, personal business and official work to form different documents like letters, wills, loan receipts, bank checks, medical certificates, working papers and contracts that can have significant financial implications.The dry ink utilized in the laser printers is called toner and it can be present in the form of powder particles or diffused in the liquid [5][6][7][8][9][10][11].…”

Interpol review of questioned documents 2016–2019

“…The black inkjet inks [ [34] , [35] , [36] , [37] ] and black toners [ [38] , [39] , [40] , [41] , [42] , [43] ] analysis is a current challenge for FDEs and some researches were published on this topic.…”

The physical Application of Non-destructive Techniques in Detection the Sequence of Intersecting Gel Ink and Printed Laser Toner Strokes

“…The ink used in a laser printer is toner and can be presented in the form of powder particles or dispersed in a liquid. The toner is a mixture consists of organic polymeric resins (main component), pigments, wax and other organic and organometallic additives [8][9][10][11][12]. In general, the luminescent materials in gel ink were often insoluble organic and/or inorganic pigment which gives the inks its sheen colors with other ingredients as solvents(as ethylene glycol), resins, lubricants, surfactants, corrosion inhibitors, sheer thinning agents, emulsifying agents and polymerization agents [3,5,[13][14][15].…”